Thompson X4 stem – issues with wide bars

Hi. I’ve read that Thompson’s X4s are a little underbuilt for wider [750 and above] bars.

Any basis for this? Or just internet rumour-mill?

Alex

sbsolute balls I reckon. I ran my 70mm X4 with 760s, then 780s and now 740s over the last 4 years.

I’ve got 750’s, ridden for 2 years, Trail/DH/4X with decent size jumps and drops, no issues. It is 50mm though and built pretty solid so perhaps the longer ones aren’t as strong!?

Ran mine with 785.
Never an issue.
My new stem is even lighter than the Thompson.

Bs rumours tbh

I never had an issue with a number of X4s over the years running bars up to 720mm. Then I put 760mm Nukeproofs on to my 90mm Thomson and you could really notice the flex. Changed to an 85mm Haven which is much stiffer. Whether you’d notice much difference when riding is debatable but the flex is there. Running 780 bars with a 70mm Haven now, solid.

Utter tosh. Did you read it in the viz?

No problem with mine on 780mm bars and I am 18 stone honking on them!
Did however find that race face ride 50mm stem and bars are like rubber so swapped thm out for RaceFace Atlas set up at full width, lovely and stiff!

Have only ever used a 50mm X4 with 760 bars there’s no flex

The X4 is also amazingly accurate it has an almost aircraft-like fit on the steerer and bars and the bolts need minimal tightening

I used to believe the “you can’t get better than a Thompson stem” thing. Seatpost too before droppers became popular. Fact is things move on and they do, Easton Havens are better.

I’ve read that Thompson’s X4s…

perhaps if you revealed your source we would be better able to comment?

I’ve got 750mm bars on my hybrid crosser on a 70mm Thomson. 25.4mm clamp. Some flex but then that’s a good thing with no bounce up front and skinny tyres.

Rode a bike with 35mm bars on last year at a demo day. They felt like scaffolding. No comfort at all.

That bloke who used to work for Freeborn Esher – Esher-shore on some forums.

I used to work down that way, so have had a few chats with him. I reckon I might get the Easton. Little bit dearer now X4s reduced on CRC.

What the heck.